Japanese biologist Yoshinori Ohsumi wins 2016 Nobel for Medicine

The Nobel Prize in Physiology or Medicine for 2016 has been awarded to Japanese cell biologist Yoshinori Ohsumi for his discoveries on how cells recycle their content, a process known as autophagy.

Yoshinori Ohsumi after hearing he had been awarded the 2016 Nobel Prize in Physiology (Medicine) / Photo: Mari Honda

''This year's Nobel Laureate discovered and elucidated mechanisms underlying autophagy, a fundamental process for degrading and recycling cellular components,'' the Nobel Prize Committee stated in a press release.

The word autophagy originates from the Greek words auto-, meaning "self", and phagein, meaning "to eat". Thus, autophagy denotes "self eating".

This concept emerged during the 1960's, when researchers first observed that the cell could destroy its own contents by enclosing it in membranes, forming sack-like vesicles that were transported to a recycling compartment, called the lysosome, for degradation, the Nobel Assembly at the Karolinska Institutet in Stockholm said while announcing the prize.

Little was known about autophagy until, in a series of brilliant experiments in the early 1990's, Yoshinori Ohsumi used baker's yeast to identify genes essential for autophagy. He then went on to elucidate the underlying mechanisms for autophagy in yeast and showed that similar sophisticated machinery is used in our cells.

''Ohsumi's discoveries led to a new paradigm in our understanding of how the cell recycles its content. His discoveries opened the path to understanding the fundamental importance of autophagy in many physiological processes, such as in the adaptation to starvation or response to infection. Mutations in autophagy genes can cause disease, and the autophagic process is involved in several conditions, including cancer and neurological disease,'' the Nobel Prize Committee  release stated.

Cells need to degrade proteins in development and in their normal lifetimes as well as during diseases like cancer, infection and starvation. Biologists knew there was a sack in the cell that seemed like a garbage dump, but few had bothered to ask much more about it. Dr Ohsumi discovered how cells control degradation of their own proteins, what genes are involved, and what happens when autophagy goes awry.

Disruptions in autophagy are thought to underlie many conditions, including cancer, infections, neurological diseases and aging. And since autophagy is a fundamental and crucial function in cells, it can be important to understand how it is controlled and what its consequences are.

''All I can say is, it's such an honor,'' Dr. Ohsumi told reporters at the Tokyo Institute of Technology, according to the Japanese broadcaster NHK. ''I'd like to tell young people that not all can be successful in science, but it's important to rise to the challenge.''